Cod sursa(job #1249469)

Utilizator deea101Andreea deea101 Data 26 octombrie 2014 23:48:34
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.95 kb
#include <fstream>
#include <vector>
#include <list>

#define NMAX 100001
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");

vector <int> G[NMAX];
list<int> coada;
list <int>:: iterator it;
int N,M,dist[NMAX],S;
bool viz[NMAX];

void bfs()
{
    int nod,i;
    while(!coada.empty())
    {
        nod=coada.front();
        for(i=0;i<G[nod].size();i++)
            if(!dist[G[nod][i]] && G[nod][i]!=S)
            {
                dist[G[nod][i]]=dist[nod]+1;
                coada.push_back(G[nod][i]);
            }
        coada.pop_front();
    }
}
int main()
{
    f>>N>>M>>S;
    int i,x,y;
    for(i=1;i<=M;i++)
    {
        f>>x>>y;
        G[x].push_back(y);
    }

    dist[S]=0;
    coada.push_back(S);
    bfs();

    for(i=1;i<=N;i++)
    {
        if(!dist[i])
        {
            if(i==S) g<<0<<' ';
            else g<<-1<<' ';
        }
        else g<<dist[i]<<' ';
    }

}